1. Field of the Invention
The present invention relates to a thin film magnetic head slider used for a magnetic disk unit, a manufacturing method therefor and an electrostatic actuator for driving a head element thereof.
2. Description of the Related Art
In recent years, the magnetic disk unit has been made compact, its performance has been highly enhanced, and its cost has been reduced. In accordance with the recent tendency, it is desired to develop a thin film magnetic head of high performance and low cost. In order to meet the demand, a horizontal magnetic head (planar magnetic head) is proposed, in which a thin film pattern surface is arranged in parallel with an air bearing surface. The reason is described as follows. In the case of a horizontal magnetic head, it is easy to form floating rails having specific shapes. Therefore, it is possible to realize a magnetic head capable of flying stably close to the disc surface, and further it is easy to reduce the portion to be machined in the manufacturing process, so that the cost can be lowered.
Examples of the conventional horizontal magnetic head slider are shown in the following publications.
IEEE TRANSACTIONS ON MAGNETICS, vol 25, p.3190, 1989, xe2x80x9cA New Thin Film Head Generationxe2x80x9d by J. P. Lazzari and P. Deroux-Dauphin. In this conventional example, a recess is formed on the surface of a silicon substrate by means of etching, and a magnetic head element is formed in the recess. In this case, the silicon substrate surface is used as an air bearing surface opposed to a recording medium. Therefore, the terminal of the magnetic head is introduced onto the back of the slider. Accordingly, a through-hole penetrating the silicon substrate is formed so as to extend from the terminal. In this example, the slider body is manufactured by means of machining.
IEEE TRANSACTIONS ON MAGNETICS, vol 25, p.3686, 1989 xe2x80x9cA New Approach to Making Thin Film Head-Slider Devicesxe2x80x9d by Daniel W. Chapman. In this conventional example, a thin film magnetic head element is formed on the substrate from the air bearing surface side, and an insulating film is made to be flat, and then a glass substrate through which a through-hole is penetrated is subjected to bonding. In this way, the slider body is made. After that, the substrate is etched for removal, and the slider body is cut by means of machining.
In the above conventional examples, it is necessary to provide the manufacturing processes of machining the slider body, assembling a head suspension to the slider individually, forming a through-hole penetrating the substrate, embedding a conductor in the through-hole, and bonding of a glass substrate. Accordingly, the manufacturing process becomes complicated.
The first object of the present invention is to provide a thin film magnetic head slider of high performance and low cost and further to provide a method for easily manufacturing the thin film magnetic head slider without forming a through-hole or bonding a glass substrate.
The second object of the present invention is to provide a thin film magnetic head slider to be easily manufactured without forming a through-hole and bonding a glass substrate, in which the magnetic head element can be highly accurately positioned so as to realize highly dense recording and enhance the reliability by adding a tracking mechanism (the tracking mechanism minutely moves the magnetic head element in a tracking direction approximately perpendicular to the moving direction of the recording medium) for the thin film magnetic head element or by adding a minute distance movement mechanism capable of minutely moving the magnetic head in the direction of a loading and unloading recording medium so that the magnetic head can approach or leave the recording medium.
The third object of the present invention is to provide an electrostatic actuator suitable for a drive mechanism to be used for the tracking mechanism or the loading and unloading mechanism in the above thin film magnetic head element.
According to an aspect of the present invention, there is provided a method for manufacturing a thin film magnetic head slider having a media opposing surface which is adapted to be opposed to a recording medium, said method comprising the steps of: providing a slider material on a surface of a substrate, or on a surface of a sacrificial layer on substrate, said surface of the substrate or said surface of the sacrificial layer being formed beforehand with a particular shape for forming said media opposing surface; forming said slider on said surface of the substrate, or on said surface of the sacrificial layer; and removing said substrate, or said sacrificial layer and substrate from said slider.
According to another aspect of the present invention, there is provided a thin film magnetic head slider adapted to be opposed to a recording medium comprising: a slider body provided on a surface of a substrate or on a surface of a sacrificial layer provided on substrate, the substrate or the sacrificial layer and substrate being separate from the slider body; a tracking mechanism supported by a stationary section of the slider body so that a movable section which is a portion of the slider body can be moved in a tracking direction approximately perpendicular to a moving direction of said recording medium; and at least an opposed magnetic pole of a thin film magnetic head element, adapted to be opposed to the recording medium, provided in a movable section of the tracking mechanism.
According to still another aspect of the present invention, there is provided a thin film magnetic head slider adapted to be opposed to a recording medium comprising: a slider body provided on a surface of a substrate or on a surface of a sacrificial layer provided on substrate, the substrate or the sacrificial layer and substrate being separate from the slider film body; a loading and unloading mechanism supported by a stationary section of the slider body so that a movable section which is a portion of the slider body can be moved in a loading and unloading direction in which the movable section of the slider body approaches and leaves a recording medium; and at least an opposed magnetic pole of a thin film magnetic head element adapted to be opposed to the recording medium, provided in a movable section of the loading and unloading mechanism.
According to a fourth aspect of the present invention, there is provided a thin film magnetic head slider adapted to be opposed to a recording medium comprising: a slider body provided on a surface of a substrate or on a surface of a sacrificial layer provided on substrate, the substrate or the sacrificial layer and substrate being separate from the slider body; said slider body comprising a stationary section and a movable section supported by said stationary section via a support spring in such a manner that said movable section can be moved both in a tracking direction approximately perpendicular to a moving direction of said recording medium and in a loading and unloading direction in which the movable section of the slider film body approaches and separates from a recording medium; and at least an opposed magnetic pole of a thin film magnetic head element adapted to be opposed to the recording medium, provided in a movable section of the tracking mechanism.
According to a fifth aspect of the present invention there is provided an electrostatic actuator comprising: a stationary section having a plurality of teeth parallel to each other; a movable section having a plurality of teeth parallel to the teeth of the stationary section; a support spring for supporting the movable section so that the movable section can be moved with respect to the stationary section in a tooth width direction; and a drive force generating section for moving the movable section to a position at which an electrostatic attraction force in the tooth width direction generated when a voltage is impressed between the teeth of the stationary section and those of the movable section, is balanced with a restoring force of the support spring.